CC BY
16LD-I-3
Physical and chemical characterization of the nanoparticles formed during laser cladding with metal powder
A. Nagy1, Sz. Kugler1'2, J. Osan2, L. Péter1, V. Groma2, A. Czitrovszky1
lWigner Research Centre for Physics, POB 49, H-1525 Budapest, Hungary 2Centre for Energy Research, POB 49, H-1525, Budapest, Hungary
nagy. attila@wigner.hu
Laser based additive manufacturing is a rapidly developing industrial technology. 3D metal printers are widely used to produce parts for prototypes where special geometries or mechanical properties are required. In a laser 3D metal printer utilizing the directed energy deposition technique, an intense laser beam melts the metal powder, which is deposited onto the substrate through a special nozzle, building the part layer-by-layer. Nanoparticles formed during intense laser-metal interactions are known to be a major concern for occupational health. Besides their chemical composition, their physical properties also make them hazardous to the operators. These nanoparticles were characterized by means ofparticle mobility spectrometry and X-ray spectroscopic techniques. We studied the physical and chemical properties of the emitted particles during the 3D printing process usingNi and Fe based metal powders. The number and the mass concentrations were measured with a Scanning Mobility Particle Counter an Sizer. Size-fractionated samples were collected by a cascade impactor, and the elemental composition of the particles was determined by total -reflection X -ray fluorescence analysis, Scanning Electron Microscopy, Energy Dispersive Spectroscopy , and microscopic X -ray fluorescence analysis in the different size fractions.The vast majority of the formed particles were found in the ultrafine region with a size below 100 nm. Our analysis showed that the ratios of the elements changed in the sampled particles compared to the original powder and the enrichment and oxidation of metals were correlated with each other. Our results confirmed that it is important to understand the processes that governs new particle formation and study its consequences on the performance of the operation and the operator's health as well.
This work was supported by the Hungarian National ResearchDevelopment and Innovation Fund under grant no. 2017 -1.3.1-VKE-2017-00039 and by European Structural and Investment Funds jointly financed by the European Commission and the Hungarian Government under grant no. VEKOP-2.3.2-16-2016-00011.
